Ganoderic Acids (GAs) are the major medicinal compounds in Ganoderma lucidum used as traditional Chinese medicine since ancient times. Ganoderic add A (GM) is the first discovered ganoderic adds reported in the literature, which is also one of most abundant triterpenoids of Ganoderma lucidum. Especially, GM has been extensively investigated in recent decades for its positive medicinal activities. However, the vibrational properties of GAs have rarely been studied or reported. In this work, we focused on the typical GM and studied the infrared (IR) and Raman spectra based on both experiments and DFT calculations. As such, we could not only achieve the assignments of the vibrational modes, but also from the IR and Raman spectra, we found that the spectral region from 1500 cm(-1) to 1800 cm(-1) is particularly useful for distinguishing different types of GAs. In addition, its dehydrogenated derivative ganoderenic acid A (GOA) was also studied, which could be identified due to its spectral feature of strong IR and Raman bands around 1620 cm(-1). This work therefore may facilitate the application of IR and Raman spectroscopies in the inspection and quality control of Ganoderma lucidum. (C) 2018 Elsevier B.V. All rights reserved.